Peter cooper hewitt



(No Model.)

P. C. HEWITT. DRYING MACHINE.

No. 526,228. Patented. Sept. 18, 1894. I

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PETER COOPER HEVITT, OF NEW YORK, N. Y.

DRYING--MACHINE.

" SPECIFICATION forming part of Letters Patent No. 526.228, datedSeptember 18, 1894.

Application iiledJ'uly 27, 1893. Serial No. 481.622. (No model.) i

To @ZZ whom it may concern:

Beit known that I, PETER COOPER HEWTTT, of New York city, in the countyand State of New York, have invented a new and Improved Drying-Machine,of which the following is a specification, reference being had to theanneXed drawings, forming a part thereof, in which- Figure l is avertical longitudinal section of my improved drying machine. Fig. 2 isatransverse section taken on line 2 2 in Fig. 1; and Fig. 3 is alongitudinal section of a modified form. l

Similar letters of reference indicate corresponding parts in all theviews.

The object of my invention is to construct a machine for drying variousmaterials, but more particularly for spreading melted glue or gelatineout into sheets, and drying and delivering the same in commercial form.

My invention consists in an endless apron supported on drums andarranged to travel through an evaporating chamber supplied with acurrent of heated air, steam, or other drying medium; also in thecombination with the endless apron, of a device for cleaving the driedsheet of glue or gelatine from the endless4 apron as it emerges from themachine, all as will be hereinafter more fully described.

In the frame A are jonrnaled the shafts a a', which carry drums b b',over which eX- tends the endless apron B, (preferably made of metah) andone of the shafts da is driven by connection with some. suitable motivepower. Uponthe frame A is mounted an evaporating chamber C, whichincloses the portion of the endless apron B which extends from the topof the drum b to the top of the drum b', and the end walls of thechamber O are provided with slots e through which the y The top of thechamber is furnished with a hot air supply D at one end, and a dischargeE for the escape of hot air and moisture absorbed from the glue carriedby the apron B.

The receiving part of the endless apron B is the part which runs fromthe drum b toward the chamber O, and above this part is arranged anozzle F, which discharges the melted glue upon the endless apron B,where the glue spreads out into a thin layer, and

`uponthe entrance of this layer of glue into the evaporating chamber O,the moisture is absorbed from the liquor by the hot air pass-` ingthrough the chamber, and to facilitate the evaporation of `the moisture,a steam coil G is placed in the bottom of the chamber C, below Atheendless apron B.

The flow of liquid glue to the endless apron B is regulated according tothe speed of the endless apron and according to the evaporating power ofthe air passing through the evaporating chamber O. The glue carried bythe endless apron B is sufficiently evaporated by the time it reachesthe delivery end of the chamber to permit of separating it from thendless apron.

"In this case, the melted glue delivered on the endless apron spreadsout in a thin layer and enters one end of the evaporating chamber,l

and is carried to the other end by the endless apron and returned in thechamber, thereby submittin g the glue to the effects of the hot airthroughout nearly the entire circuit of the apron. In this case, the airenters through the supply D', and a part of it emerges through adischarge E', while another portion passes out through the apron slotsc. By this arrangement, any chips that might fall off from the driedglue carried by the lower portion of the endless apron are blown awayfrom the partly dried glue toward the driedglue and thus prevented fromsticking and impeding` the process of evaporation.

In the case of the form shown in Fig. 1, where it is desired to deliverthe finished product at the end of the machine farthest from the supply,the air supply D is moved forward to the position shown in dotted lines,the operation with this modiication being the same as that described inconnection with Eig. 3, that is to say, the blast of air through the airsupply D is divided, one portion passing to- IOO ward the supply end ofthe endless apron, and the other passing in the opposite direction.

The machine may be made of different lengths to adapt it to drying filmsof different thickness. I have found by experiment, that while a filmfrom .002 to .005 of an inch in thickness can be rapidly run through amachine having a length of ten or twenty feet, the drying of a thickerfilm requires a length of time much greater than would be proportionateto the increased thickness of the lilm, owing to the slow transmissionof moisture from the interior of the film to the exterior. I have alsofound that ytoo rapid evaporation from thick lms of glue causesebullition, which produces bubbles, giving the glue or other material aninferior appearance when dry, Whereas in the case of thin films theevaporation proceeds without forming bubbles, leaving the glue perfectlyuniform in appearance. 1

Having thus described my invention, I claim as new and desire to secureby Letters Patentp 1. In a machine for drying thick, gelatinoussubstances such as glue, the combination of ahorizontal endless apronsupported on drums and arranged to travel through an evaporatingchamber, an air supply pipe located between the ends of the evaporatingchamber for directing a current of heated air down upon the substancebeing dried, a device `for delivering the material to be dried to theendless apron, and a device for cleaving the dried sheet of materialfrom the endless apron, the air current being divided by contact withthe material being dried, the air supply pipe being arranged relative tothe endless apron and the material carried thereon, so that the aircurrent flowing in the direction of the motion of the material beingdried will carry away any loose chips which might otherwise be carriedinto the undried material, substantially as specied. l

2. In drying apparatus, an endless apron for carrying the material to bedried, and a divided air blast, one portion thereof being directedtoward the supply end of the endless apron, the other portion beingdirected toward the delivery end of the endless apron, as specified.

PETER COOPER HEWITT.

Witnesses:

F. W. HANAFORD, EDGAR TATE.

